Method for cleaning a pipe

ABSTRACT

A method for cleaning a pipe using a swab that can be made of one or multiple tires connected to one or more cables and pulled through the host pipe during the cleaning process. The cables are attached to rigid plates mounted in the central opening of the tire. The method provides an effective and low cost method to remove debris and mud particularly from underground pipe.

This application is a divisional of U.S. application Ser. No. 08/975,858filed Nov. 21, 1997, now U.S. Pat. No. 5,950,271.

FIELD OF INVENTION

The invention relates to a swab that is used to clean and plug pipelines.

BACKGROUND OF THE INVENTION

In the course of maintaining and rehabilitating utility lines includingpipe lines, it is sometimes necessary to clean or swab these lines inorder to ascertain their condition. Debris can build up and collect onthe interior walls of an existing pipe. This debris must be cleanedbefore any repairs or rehabilitation can be made. Additionally, it issometimes necessary to plug these lines in order to perform inspectionsor repairs. However, many of these lines cannot remain blocked or out ofservice for very long.

SUMMARY OF THE INVENTION

A swab has been developed for use in cleaning utility lines. The swabcan be made of a flexible, circular member such as a tire having a frontside with a front lateral sidewall, a rear side with a rear lateralsidewall, an exterior surface, an interior cavity and a central orifice.A steel plate is concentrically mounted against each lateral sidewall ofthe tire. The steel plates are attached to each other by four connectingrods which engage both plates by extending through both the tire and theplates. A yoke attachment point fixed to each end of connecting rods anda flexible yoke is attached to each point. Two cable attachment pointsconnect all of the yokes on each side of the tire. In one embodiment, aflow pipe with a valve and valve actuator extends through the centralorifice of the tire.

In alternative embodiments, the exterior surface of the tire could besmooth or a raised tread. Also, the interior cavity of the tire could befilled with a foam such as a low density foam. In another embodiment,three tires are aligned in a side by side arrangement to form a swab.Two steel plates are concentrically mounted against the front and rearsidewalls of the exterior tires in the arrangement.

A method is claimed for cleaning a host pipe with both a single tireswab and a multi-tire swab. The steps include positioning the swab inthe host pipe, connecting each cable attachment point to a cable, andpulling the swab through the host pipe.

A pipe plug has been developed for use in plugging pipe lines. The pipeplug comprises a tire having a front side with a front lateral sidewall,a rear side with a rear lateral sidewall, an exterior surface, aninterior cavity and a central orifice. A tire rim with an axle connectoris mounted with the central orifice of the tire. A steel plate coversthe axle connector. A valve stem extends from the tire through the tirerim. An air tube which provides air from a compressed air source isconnected to the valve stem. Four connecting rods engage and extendthrough the tire rim. A yoke attachment point fixed to each end ofconnecting rods and a flexible yoke is attached to each point. Two cableattachment points connect all of the yokes on each side of the tire.

In an alternative embodiment, the exterior surface f the tire could besmooth. A further embodiment includes bladder disposed in the interiororifice of the tire to old the compressed air. In another embodiment,two tires are used to form a dual-tire plug. A pipe which extendsthrough the tire rims connects the two tires. A transfer tube connectsthe interior cavities of each tire so that a single source of compressedair may be used to inflate the plug. A flow orifice is located insidethe tire rim of each tire and a valve with a valve actuator is locatedin the pipe which connects the tires.

A method is claimed for using both the single tire plug and themulti-tire plug. The steps include positioning the plug within the hostpipe, inflating the plug until the exterior surface of the plug contactsthe host pipe, and deflating the plug when it is to be removed.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a perspective view of a swab.

FIG. 2 is a cut-away side view of a swab.

FIG. 3 is a cut-away side view of a multi-member swab.

FIG. 4 is a frontal view of a swab with a flow pipe.

FIG. 5 is a cut-away side view of a swab with a flow pipe.

FIG. 6 is a perspective view of a swab with a flow pipe, valve and valveactuator.

FIG. 7 is a perspective view of an operation using a swab with a flowpipe.

FIG. 8 is a perspective view of an operation using a swab with a flowpipe.

FIG. 9 is a perspective view of an operation using a swab with a flowpipe.

FIG. 10 is a cut-away side view of a plug.

FIG. 11 is a frontal view of a plug.

FIG. 12 is a cut-away side view of a multi-member plug.

FIG. 13 is a perspective view of a multi-member plug with a valveactuator.

FIG. 14 is a cut Away side view of a multi-member plug with a valve andvalve actuator.

FIG. 15 is a perspective view of an operation using a plug.

FIG. 16 is a perspective view of an operation using a multi-member plug.

FIG. 17 is a perspective view of an operation using a multi-member plugwith a valve.

FIG. 18 is a perspective view of an operation using a multi-member plugwith a valve.

FIG. 19 is a perspective view of an operation using a multi-member plugsand a transfer pipe.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following is a description of the invention and figures. Indifferent figures, the same elements are represented with the samenumbers.

FIG. 1 shows a detailed perspective view of a tire swab 10. The tireswab 10 includes a tire 12, a rigid plate 22a, four yoke attachmentpoints 26a-d, four yokes 28a-d, and a cable attachment point 30a.

The tire itself can be a new or used tire. The use of old tires is a keybenefit of the claimed invention. Old tires which are no longer usableon vehicles present a significant environmental disposal problem. Theuse of recycled tires can be a significant economic benefit inmanufacturing. Tires that are damaged from use as a swab can be easilyand quickly replaced at a low cost.

The tire 12 is selected for a size to fit within the diameter of thehost pipe which will be cleaned. The tire 12 can compress whenencountering an obstruction which would lodge a rigid swab. As shown,the exterior surface 14 of the tire 12 has a rough, raised tread.However, the exterior surface 14 may be smooth so that it contacts thewall of the host pipe more fully. The exterior surface 14 of the tire 12may be made smooth and the outside diameter of the tire 12 can beaugmented by any re-treading or re-capping process for used tires. Inre-capping the tire, different types of materials may be used to producea different type of texture on the exterior surface 14 of the tire 12.

While embodiments which use tires are shown in the drawings, anysuitable alternative could be used. Such an embodiment would have acircular shaped member to contact the walls of the host pipe to becleaned. Furthermore, this member would also have the necessaryflexibility to compress or deflect around obstacles in the same manneras a tire.

The rigid plate 22a is concentrically mounted against the front lateralsidewall 18a of the tire covering its central orifice 20. Because thetire rim has been removed, the rigid plate 22a provides a support to thetire and an attachment point for the yokes 28a-d which will pull thetire swab 10 through the host pipe. The rigid plate 22a is normally madeof steel, but it can be made of any material which provides sufficientstrength to support the apparatus. The size of the rigid plate 22a isselected to allow the deflection necessary to avoid lodging the tireswab 10 on any obstructions.

The yoke attachment points 26a-d serve to provide an attachment pointbetween the yokes 28a-d and the tire swab 10. They are attached to theend of connecting rods 24a-d which connect the rigid plate 22a to thetire 12. While four are shown, the yoke attachment points may vary innumber according to the number of yokes. Also, the location of the yokeattachment points may vary depending on the desired distribution of thepulling force on the tire swab 10. While the yoke attachment points26a-d are shown as loops, they may be of any other suitable attachmentmeans.

The yokes 28a-d serve to distribute the pulling force of the cable 45 tothe tire swab 10. They are made of any material capable of withstandingthe applied pulling force, including materials of different degrees offlexibility. The number of yokes 28a-d may vary depending on how widelythe pulling force is to be distributed on the tire swab 10.

The yokes 28a-d are connected to the cable 45 by a cable connectionpoint 30a. The cable connection point 30a pulls all of the yokes 28a-dtogether to a single point to transfer the pulling force applied by thecable 45. The cable connection point 30a is shown as a loop, but anyother suitable attachment mechanism could be used.

FIG. 2 shows a cut-away side view of a tire swab. A second rigid plate22b is shown mounted on the rear lateral sidewall 18b of the tire 12.The interior of the tire swab 10 shows the connecting rods 24a-b (24c-dare not shown) and the interior cavity 16 of the tire 12 which is filledwith a low density foam 32. Also shown is an arrangement of yokeattachment points 26e-f (26g-h are not shown), yokes 28e-f (26g-h arenot shown), and a cable attachment point 30b. This arrangement isidentical to the arrangement mounted on the rigid plate 22a in FIG. 1described previously. The connecting rods 24a-b (24c-d are not shown)extend through the tire 12 and both rigid plates 22a and 22b. Eachconnecting rod 24a-b has a yoke attachment point 26a-b and 26e-f on eachend.

The interior cavity 16 of the tire is shown filled with a low densityfoam 32 to provide support to the tire 12. However, the tire 12 will beable to compress to a certain degree while it is pulled through the hostpipe. While a low density foam 32 is shown, any material may be used tofill the tire 12 depending on its characteristics and the desiredeffect. For example, if additional weight is desired to stabilize thetire swab 10, sand may be used to fill the tire 12. Also, air could beused to provide better contact between the exterior surface 14 of thetire 12 and the wall of the host pipe. This provides a more efficientswabbing.

The rigid plate 22b and the arrangement of yoke attachment points 26e-f,yokes 28e-f, and cable attachment point 30b shown in FIG. 2, are analternative embodiment of the tire swab in FIG. 1. The tire swab asshown in FIG. 1, has a tendency to turn within the host pipe when it isbeing pulled due to the pressure of the flow in the host pipe. Attachingthe tire swab 10 to another cable (not shown in FIG. 2) on the otherside of the tire swab 10 provides additional stability and reduces thetendency to turn. Additionally, if the tire swab 10 becomes wedged inthe host pipe, the direction of the swab can be reversed by the othercable. This will avoid a costly stoppage of work and possible excavationto retrieve the swab.

An alternative embodiment consisting of a multi-tire swab 34 is shown inFIG. 3. The structure of the apparatus is essentially the same as shownin a single tire swab except that three tires 14 are used instead ofjust one. The tires 14 are identical to each other and are placed sideby side with the connecting rods 26a-b (26c-d not shown) extendingthrough each of them. While three tires are shown, any number could beused depending on the desired result.

As discussed previously, a single tire swab 10 has a tendency to turnwhile being pulled within the host pipe. A multi-tire swab 34 will notturn in the host pipe because of the length of the apparatus. In somecircumstances, it is necessary to use a multi-tire swab 34 so as not toimpose too great a load on the wall of the host pipe when a turn ordeflection is encountered.

FIG. 4 shows another embodiment where a tire swab 10 that has a flowpipe 36 with an orifice 20 located in the center of the tire. A cut awayside view is shown in FIG. 5. FIG. 6 shows a valve 38 located within theflow pipe 36 and a valve actuator 40 that is used to control the openingand closing of the valve. The other structures of the tire swab 10 shownin FIGS. 4, 5 and 6 are the same as shown in FIG. 1.

The flow pipe allows the flow in the host pipe to pass through theorifice while the tire swab 10 is being pulled. This reduces thepressure on the swab and the tendency to turn within the pipe. Becausethe flow through the orifice 20 is moving at a greater velocity thanthrough the host pipe, it can be used to create a jetting action tocarry away the debris collected by tire swab 10.

FIGS. 7, 8 and 9 show the tire swab 10 with a flow pipe 36 being used toclean a host pipe 50. In FIG. 7, the tire swab 10 is lowered into theexcavated access area 48 by a winch 44 mounted on a vehicle 42a. Anothervehicle 42b with a winch 44 is located at the far end of the segment tobe cleaned. In this case, access to the host pipe 50 is provided via anexisting manhole 46.

Once the tire swab 10 is positioned within the host pipe 50, it isconnected to each vehicle 42a and 42b and pulled through the pipe. Asshown in FIG. 8, the debris 54 within the host pipe 50 is collected infront of the tire swab 10 and pushed toward the manhole 46. At themanhole 46, it is removed by a vacuum mechanism or other suitable means.The flow pipe 36 allows the host pipe to remain in service while beingcleaned. The flow 52 in the host pipe 50 is able to pass through theflow pipe 36 in the tire swab 10 while the cleaning is in process.

Another use of the claimed invention is as a plug to block the flow in ahost pipe. FIG. 10 shows a cut-away side view of an embodiment of asingle tire plug 56. The structure of the apparatus is essentially thesame as the tire swab, except that a circular tire rim 58 is mountedwithin the tire 90 instead of rigid plates mounted against thesidewalls. The tire rim 58 is a conventional type rim for mounting thetire on a vehicle. It has an axle connector 62 for attachment to such avehicle. An alternative embodiment uses a pre-fabricated rigid supportin place of the tire rim. It should be made of a material of sufficientstrength to fully support the tire 90.

A valve stem 60 extends from the interior cavity 94 of the tire 90through the tire rim 58. The interior cavity 94 is empty so that oncethe plug is positioned, it can be inflated with air until the exteriorsurface 92 of the tire 90 is in solid contact with the wall of the hostpipe. The valve stem 60 is connected to an air tube 64 which uses asource of compressed air to inflate the tire 90. The valve stem 60 isalso used to deflate the tire 90 when the plug is to be removed from thehost pipe.

An alternative embodiment uses a bladder which is located in theinterior cavity 94 of the tire 90. The bladder holds the compressed airwhich is used to inflate the tire 90. In this embodiment, the valve stem60 would extend into the bladder instead just the interior cavity 94.

FIG. 11 shows a frontal view of the tire plug 56 with a rigid cover 66aattached over the axle connector 62 of the tire rim 58. This completesthe seal of the apparatus and thus block the flow. The rigid cover 66ais normally made of steel, but it could be made of a material ofsufficient strength to withstand the applied forces and maintain a seal.If a pre-fabricated support is used instead of a tire rim, the axleconnector will not be present and so the rigid cover 66a will not benecessary.

An alternative embodiment of a tire plug is shown in FIG. 12. A cut-awayside view of a dual-tire plug 68 shows two single tire plugs aspreviously described, which are connected by a pipe 72 and a transferair tube 70. While a pipe 72 is shown, any other suitable device totransfer the flow through the plug could be used. The dual-tire plug 68uses a second tire as a back-up should the first tire leak. The transferair tube 70 serves to transfer air pressure between the tires so thatone source may be used to inflate both. While two tires are shown inFIG. 12, any number could be used as the circumstances require.

Another embodiment of the dual-tire plug is shown in FIGS. 13 and 14.Two flow orifices 74a and 74b are located in each rigid support whichallow the flow into the pipe 72 which connects the tires 92. The pipe 72is separated into segments which are connected by a pair of flanges 76.The flanges 76 are attached to each other by flange connectors 78 whichmay be a nut and bolt, a rivet or other suitable connectors. A valve 108and valve actuator 110 is located at the junction of the flanges 76. Thevalve 108, which is controlled by the valve actuator 110, opens andcloses to pass or block the flow in the pipe 72. The valve 108 may be a"butterfly valve" or any other suitable type of valve which issufficient to block the flow within the pipe 72.

FIG. 15 shows a single tire plug 56 in use in a host pipe 122. Thesingle tire plug 56 is placed upstream of an excavated access area 120.An air compressor 80 on the surface is used to inflate the tire plug 56with an air tube 64. Once the flow 124 is blocked, the work may proceedin the excavated access area 120. FIG. 16 shows an identicalinstallation using a dual tire plug 68. It this embodiment, theadditional tire provides additional protection if the first tire shouldleak.

FIGS. 17 and 18 show an installation with the dual tire plug 68 with thevalve 108 to control the flow 52. In FIG. 17, the valve 68 is closed andthe flow 124 is blocked so that work may be done in the excavated accessarea 120. Once the work is completed, the valve 68 can be opened and theflow 124 resumed in the host pipe 122. The flow 124 may be resumed whilekeeping the dual tire swab 68 in place. This has the advantage ofshutting off the flow 124 at a later time without the expense ofre-installing another plug.

FIG. 19 shows another use of the dual tire plug 68. In thisconfiguration, two dual tire plugs 68 are installed in the host pipe 122on either side of the excavated access area 120. A transfer pipe 86connects the tire plugs 68. This allows the work in the excavated accessarea to proceed while the host pipe 122 remains in service. The transferpipe 86 can remain in place indefinitely while the work is continuing.

What is claimed is:
 1. A method for cleaning a host pipe with a swabcomprising steps of:positioning the swab comprising at least oneflexible circular member with a rigid plate mounted on the flexiblecircular member with at least one cable attachment point on at least oneof each side of the rigid plate inside a host pipe; connecting a cableto a cable attachment point; pulling the swab by the cable through thehost pipe; and cleaning the host pipe interior with the swab.
 2. Themethod of claim 1 wherein the swab comprises a single tire.
 3. Themethod in claim 1 wherein the swab is a multi-tire swab.
 4. The methodof claim 1 further comprising the steps of:connecting a second cable toan attachment point on a side of the swab opposite an initial cableattachment; and cleaning the host pipe by pulling the swab through theinterior of the host pipe by both cables, alternatively.